Psychological and hormonal effects on cardiovascular regulation

The cardiovascular system is subject to various dynamical processes enabling adaptive changes under a wide range of circumstances. The resultant changes allow rapid cardiovascular responses to a number of physiological and psychological factors, including stress. Currently, a wide variety of research avenues are used in the pursuit to better understand the effects and consequences of stress. It is well established that anticipation or exposure to stressors results in activation of two major endocrine systems, the hypothalamic-anterior pituitary-adrenocortical axis and the sympatho-adrenomedullary axis. Together, these systems regulate physiological and behavioral stress processes, which are overall adaptive in the short term, but can be maladaptive in the long-term in vulnerable individuals. Our social and physical environment exerts strong effects on the brain and the body through the neuroendocrine, autonomic, and immune systems (McEwan, 2007). The ability of the brain and the body to adapt to acute and chronic mental stress is an increasingly important topic in the modern world. Chronic mental stress can have a serious impact on physical as well as psychological health in vulnerable individuals (Cohen, Janicki-Deverts, Miller, 2007). Indeed prolonged mental stress has been linked to several cardiovascular diseases (Dimsdale, 2008; Hjortskov et al., 2004). In this talk, I will provide a brief overview of the evidence pertaining to the patterns of bidirectional communication between the brain, the autonomic, and cardiovascular systems via neural and endocrine mechanisms following stress exposure. In addition, somatic and behavioural response variability that appears to moderate the effects of mental stress on stress systems activation and cardiovascular response will be discussed. The negative health outcomes associated with mental stress are a matter of growing concern. Large sections of the general public are likely to experience periods of mental stress and this highlights the importance of assessing the effects of stress on multiple systems, including hormonal, cardiovascular and neural responses. A multidisciplinary approach is needed to further our understanding about the effects of stress on various systems and to identify mechanisms and vulnerabilities leading to disease. A more complete understanding of the individual differences in the response to stress will help to explore ways in which resilience can be harnessed to improve individual health outcomes. References McEwen, B.S. (2007) Physiology and neurobiology of stress and adaptation: Central role of the brain. Physiol Rev 87, 873–904. Cohen, S., Janicki-Deverts, D., Miller, G.E. (2007) Psychological stress and disease. JAMA 298,1685–1687. Dimsdale, J. E. (2008) Psychological stress and cardiovascular disease. Journal of the American College of Cardiology 51, 1237–1246. Hjortskov, N., Rissen, D., Blangsted, A., Fallentin, N., Lundberg, U., and Søgaard, K. (2004) The effect of mental stress on heart rate variability and blood pressure during computer work. European Journal of Applied Physiology 92, 84–89